CURLOPT_FRESH_CONNECT man page
CURLOPT_FRESH_CONNECT — force a new connection to be used
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_FRESH_CONNECT, long fresh);
Pass a long. Set to 1 to make the next transfer use a new (fresh) connection by force instead of trying to re-use an existing one. This option should be used with caution and only if you understand what it does as it may seriously impact performance.
Related functionality is CURLOPT_FORBID_REUSE(3) which makes sure the connection is closed after use so that it won't be re-used.
Set fresh to 0 to have libcurl attempt re-using an existing connection (default behavior).
curl_easy_setopt(3), CURLOPT_FORBID_REUSE(3), CURLOPT_PIPEWAIT(3), CURLOPT_URL(3), libcurl-tutorial(3).